Title :
Demonstration and Study of Photovoltaic Performances of InGaN p-i-n Homojunction Solar Cells
Author :
Zeng, Sheng-Wei ; Cai, Xiao-Mei ; Zhang, Bao-Ping
Author_Institution :
Dept. of Phys., Xiamen Univ., Xiamen, China
fDate :
5/1/2010 12:00:00 AM
Abstract :
We reported on the InGaN p-i-n homojunction solar cells with In contents of 0.02 and 0.12. Under the same illumination of Xe lamp, In0.02 Ga0.98N cell exhibited a fill factor (FF) of 67.8%, a higher open-circuit voltage (Voc) of 2.15 V while In0.12Ga0.88N cell showed a FF of 64.8% and a lower Voc of 1.35 V. The measurements of atomic force microscopy (AFM) images and leakage currents revealed that V-shaped defects, which are known to cause the increase in reverse current, were the main factor dominating the Voc of In0.12Ga0.88N cells. Short-circuit current versus open-circuit voltage (Jsc - Voc) curves were consistent with the characteristics expected from the current-voltage equation. Relative external quantum efficiencies (EQEs) were also measured and showed strong dependence on V-shaped defects. These results indicate that defects in bulk InGaN has a negative impact on the photovoltaic performances of solar cells based on III-nitrides.
Keywords :
III-V semiconductors; atomic force microscopy; indium compounds; leakage currents; photovoltaic effects; solar cells; InGaN; V-shaped defects; atomic force microscopy; external quantum efficiency; leakage currents; open circuit voltage; p-i-n homojunction solar cells; photovoltaic performance; short circuit current; voltage 1.35 V; Atomic force microscopy; Atomic measurements; Force measurement; Lamps; Lighting; PIN photodiodes; Photovoltaic cells; Photovoltaic systems; Solar power generation; Voltage; Homojunction; InGaN; solar cell;
Journal_Title :
Quantum Electronics, IEEE Journal of
DOI :
10.1109/JQE.2009.2039197